The scanning system is a image processing tool popularly employed for scanning the image of documents, photographs, and even objects. The image is transferred to accessible signal or data for the computer. The document is illuminated by a light source during scanning. The image is then transferred upon a CCD (Charge-Coupled Device) set through a set of lenses or a CIS (Contact Image Sensor) set. The CCD set or the CIS set transforms the image to accessible signals. In general, the scanning systems can generally classified into three categories, including a handhold scanning system, a sheet feeding scanning system, and a flatbed scanning system.
For receiving large enough documents like eight and a half inch wide A4 document, conventional scanning system is big in volume and occupies a large space. The space occupied is even larger especially for the flatbed scanning system. Most of the scanning system is an isolated peripheral device to a computer system. The isolated device makes it an inefficient peripheral in space and inconvenient to use. In recent years, a scanning system which can be incorporated or integrated with a desktop computer, a laptop computer, or other peripherals like monitors, printers, or keyboards are developed to save more space.
The sheet feeding scanning system is one of the most space-efficient system. The conventional sheet feeding scaring system has a paper guide or a tray for feeding or placing a document. The scanning system with a paper guide generally cost additional volume space for the large volume of the paper guide. The open design of the scanning system suffers the pollution problem of dust and particles and the image quality is influenced. Some of the system use only rollers without paper guide to save more space. However, the system without a paper guide is not convenient to use and cause the problem of tilted document feeding. In the scanning system with a tray for place documents, the complicate mechanical construction makes it hard to design and manufacture. The maximum acceptable length of the documents is also limited with the limited tray size.